Means for automatic tightening of fastening hoops



May 23, 1933. J. P. M. MALLEVILLE 1,910,115

MEANS FOR AUTOHATiC TIGH'i'ENING OF FASTENING BOOBS v Filed July 13. 1929 I I "/1 Z1" 7 spring being replaced by an india-rubber 85 Fig. 5 is a detail Patented May 23,1933

PATENT OFFICE JEAN PAUL MARIE HABLEVILLE, OF PARIS, FRANCE ms iron amm'rzc rren'mnme or rasrnnmo aoors Application filed J'uly 18,'1929, Serial No. 878,168, and in France July 27, 1928.

The present invention relates to an auto matic tightening device acting either alone or in combinations with the ordinary tightening means and having the purpose, es-

5 pecially, to ensure a permanent contact and to prevent any play, between the hoop and the object fastened by it.

This tightening device is constituted by elastic means (spring, india-rubber and so 10 on) acting upon both extremities of the hoop, so as to distance them if they are crossing themselves, and to draw them nearer to each other if they are not crossing themselves.

The invention will be better understood in the course of the following description referring to the drawing appended, which illustrate, in the way of examples, a few embodiments of the subject-matter of the inac vention.

as drawing its two extremities closer to each other;

Fig. 3 illustrates a hoop with crossed extremities kept apart from each other by means of a spring surrounding the hoop;

Fig. 4 shows a similar embodiment, the

. ng; 1g. 5 represents an embodiment for amplifying the tension;

lan of the same. Fig. 6 shows another embodiment permitting the amplification of tension;

Fig. 7 illustrates a device or element for instantaneous tightening, tensioned and previous to its introduction between the hoopextremities, and

Fig. Sshows the same after introduction.

According to the first embodiment, the

tightening device is constituted by a spring 'r removing from each other the two extrem' ities e, e, crossing each other, of the hoop or strip a.

According to the second embodiment-Fig.

2the' extremities e, e, do not cross themselves and the spring r guided by a bolt 22 the invention ma draws, on the contrary, the said extremities toward each other.

In both these embodiments the sprin s work as compression springs but they cou d obviously act in the way bf draw-springs, as shown in Fig. 3,.where the s ring surrounds the hoop and tends to distance the two hoop-extremities.

The spring 1- can be replaced by any other elastic means such as india-rubber strings. In this way the fore-cited embodiment could be modified according to Fig. 4, the two extremities e, e of the hoop being accordin' to this modification removed from eac other by an india-rubber rope r surrounding the hoop c.

The tightening means in accordance with be of the form shown in Fi res 5, 5, w ich I will now describe. A substantially U-shaped frame d has at its closed end a bottom ortion 02" and. an outstanding cross bar Said bottom portion has an opening 1.?" throu h which one end portion of the band 0 slldably passes, said band-having at said end an out-turned ortion c'-. A coiled spring 1' is arranged etween the members d and e and its ends are fastened thereto. The sides of the frame (I at the 0 en end of said frame are provided with bearings in which a vwinding pin a is mounted for rotation. The end .e of band or collar 0 is secured b any suitable means to the in a so that said end may be wound on said pin when the latter isfturned. As here shown said end ofthe band or collar has an inwardly. turnedportion f which is fitted in a corresponding radial slot in the pin. Any suitable means ma .be provided to prevent casual reverse rotation of the pin. For the purposes of this specification a ratchet wheel a is provided on the pin and the frame is provided with a pawl w" for engagement with the ratchet wheel. The pin is also here shown as provided with a'noncircular head a so that it ma be readily turned as by means of a suitab e wrench.

When the device is inposition .on the tube to be t ghtened, the'axis a is rotated to wind. up the. part e several turns the'rearound whereb the spring a is fully: compressed and a perfectly tight joint is effected by the collar 0. I

If the collar gives for somereason, the

compensator spring 1' takes up the play be- ;cause it is disposed in series with the tightening device actuated by turning the pin a.

The sprin 1' thus acts on the end (1' of the device g and on the end spreading them apart to increase the tightening of'the 1 collar and provide automatic take up for play in case of partial loosening.

To give powerful and always equal tight: ening and even and increasing pressure, the tightening means may be obtained by the 15 use of lever arms to amplify the tension. The spring r can thus work under tension on both arms I and 1 (Fig. 6) connected to the extremities e and ef of collars c. The spring is secured at one end to the point 20 of articulation of these 'arms or levers, is fixed, at the other part, to one of the branches of the hoop. On the relative length of these arms or levers can depend a determined amplification of the spring ten- 25 sion, in such manner that notwithstanding the decreasing tension of the spring a constant tightening or even increasing tightening power (depending solely on the length of the arms) is obtained, whose intensity 30 is greatest at the last moment of tightening, viz. near the stretched position of thesetwo arms.

- This embodiment represents hence the application of a half-parallelogram completed by the extremities of the hoop itself.

This amplificationof power is obviously at the expense of the length of the lever arm, vizpthat when the arms are, at the end of the stroke, near the horizontal position (never completely realized), the displacement of the hoop-extremities is very small but the efiort enormous.

By this expedient the drawback common to tile preceding embodiments is dispensed wit It goes without saying that the spring, instead acting as a draw-spring extensioncould be disposed so as to act' as compression--or traction-spring, which is only a question of detail, the final result being always the same.

The amplification of the power could-be obtained also bymeans difi'erent from said levers, for example by a cam of an approriate design; the example represented has en chosen simply by its simplicity to show what the inventive idea consists in, which admits very manifold deviations from this example.

In order to obtain an instantaneous tension of the hoop, use can be made of elastic bodies tensioned previously and maintained in this position by any suitable contrivance, so as to be freed from the latter after their insertion into the hoop and at the moment.

of tightening the same, so as to develop at this moment only and automatically the necessary tightening efiort.

Fig. 7 shows diagrammatically 'onl the spring 1" compresse by a ligature 01 any kind 1) whose sectioning (Fig. 8) permits escaping of the spring.

It is of course possible to replace the sprin by an india-rubber block, eventually arme surround the part to be fastened, once or several times.

What I claim, is: a 1 1, In combination with a tightening band and to use as ligature, screws, pins, studs, pawls, dogs, fusibles and so on.

forming a hoop and having itsends crossed and extending in opposite directions, elastic means between the extremities of said band, and arran ed on the outer side of the hoop, to move t em in the required directions to reduce the diameter of the space encircled bzthe band and tighten said band around an o ect that may be in said space. 2. In combination with a tightening hoop, two links articulated to each other and with parallelogram.

In witness whereof I aflix my signature. JEAN PAUL IARIE HALLEVILLE.

their free ends to the extremities of the 1 

